Thermostat-controlled alarm



March 19,1929. C, G. ROWAN 1,795,931v

THERMOSTAT coNTRoLLED ALARM Filed April 50, 1928 2 Sheets-Sheet- L `lllllllII-llllllllll l IN VEN TOR.

f3/CM.

AT oRNEYs.

March 19, 1929. c. G. RowAN THERMOSTAT CONTROLLED ALARM vFiled April 50, 1928 2 Sheets-Shet IN VEN TOR.

Patented Mar. 19, 1929.

UNITED y PA'riezisiT- oFFicE.'

THERMOSTAT-CONTROLLED ALARM.

Application filed April co,

rlhis invention relates to thermostatcontrolled Alire alarm mechani'smvvhereby an alarm shall be sounded upon the thermostat reaching a predetermined temperature and is primarily intended for use in residences, hotels and factories not equipped With automatic sprinkler systems or other lire protection apparatus. Y

A further object of the invention is to produce an valarm mechanism which maybe used in combination With a remotely located thermostat for effecting operation yof the alarm.

A still further object is to Vproduce va strong, durable7 etcient and inexpensive construction of the type mentioned; and in order that it may be fully understood, reference is to be had to theaccoinpanying drawings, in which: l

Figure 1 is a face view of an apparatus einbodyiiig the invention.

Figure 2 is a side elevation ofthe same.'V

Figure -3 is an enlarged top plan'vievv with the glass and dial removedand With a part of the franie and base broken away to illustrate parts otherwise hidden.

Figure 4 is a side elevation, partly in'sec tion of the construction as shown in Figure 3.

Figuren is an enlarged detail of the electrically-operated trip mechanism operated by a remote thermostat.

lii the said.drawings7 Where like referenc characters identify corresponding parts in all of the g'ures, 1 indicates a base plate provided with a marginal iiange 2 on which a' easing 4 is removably mounted. Mounted on 'the base plate 1 is a spring-motor carryii'ig-'"raiiie comprising a top plate 5 and a botn toni plate (l secured together by a series kofretainiiig and spacing bolts and sleeves 8, theiipper pito/5 being formed with a pair of transversely extending projecting' ribs 9 acting as sugports for a dial plate 10 provided v`with Suitable teinjieratiiiieindicating marks 11. 1n abutment with a face of the dial 10 is a soacinc' collar or rinol 12 affainstwhich av l c zo e glass plate 13 isheld for means of a flange 14 on the casing 4. rlhe base plate 1 on its side opposite from the spring-motor frame is integrally formed With a tubular internally threaded extension 15 providing a support i for a one 1f: said 0'ono' having a stem not ib ei i ta k3 shown) threaded into said extension. VThe gong is preferably ofsubstantially the diameter of casing 4 ,so-that it shall provide a hous'- ing` for mechanism hereinafter described. j

Mounted between the upper plate 5 and the through and joui'naled in the base 1-.

192s. seriai No. 274,061.

enmeshed with a pinion 20, said pinion being. keyed on a shaft 2l journaled at one end in the plate 5 and at its other end projecting The shaft 21 at its outer end carries a star-Wheel 22 eo-operating with a dog 23 oseillatably mounted on a fiXed shaft 24 carried' by the base 1, said dog being integrally formed With a clapper 25 for operation of the gong.` 4The clapper 25 isy operated in one direction by the V`*dog 23 and starvvheel22 and in the other direction by a retractile spring 26A secured vto a pin'27 carried by the base 1. The shaft r18 on the outer face ofthe base plate 1 carriesa detent Wheel 28 Which is prevented from rotation in one direction by a lspring dog 29 held in engagement with the Wheel by a spring V30, so that the motor cannot unwind during a winding operation as will be readily understood. Enmeshed with the gear Wheel 19 is a pinion 31 on ashaft 22 having its opposite ends journaled in the plates 5 and 6, and said shaft carries a-large gear 33 enineshed With va pinion 34 on a shaft 35 joiirnaled at its opposite ends in said plates. The shaft'fl also carries a gear wheel 36 enmeshed with a pinion 37 on an escapeinent shaft 38 journaled between the plates 5 and 6. The shaft 38 carries an escapement Wheel 39 controlled by pallets 4() on van oscillating stop lever 41 integrally formed With a shaft 42 journaled between plates 5 and 6.'

From the above description and referring to Figure 3, it 'will be evident that with the pallets-in locked position as illu'strated",` the vspring motor 17 is held against operation, but

that upon release of rthelock lever 41 the escapeinent Wheel 39 Will befreed for operavtion and the train of gearing will rotate, the

drive gear 19 effecting operation'of the operating shaft 21. To provide thermostat control mechanism to trip the locking or stop leve'r'41, a shaft 42EL is journaled at its lower end in the plate' and projects through the Yupper plate 5 and the dial 10, and at its upper end-carries an indicating finger 43 for regis-k tering With the dial marks 11. Thev end of the shaft 42 is squared 'as at 44 and secured i tosaid squared portion is one end of a spi-ing' thermostat 45, the opposite end of said spring thermostat being secured to an anchorl 46 carried by the plate 6. Mounted on the sliaft 42 above the thermostat spring is a cani 47 having a notch 48.

Journaled between the plates 5 and G is a shalt 49 formed integrally with a catch lever 5() normally having one end in abutment with,

the end of the loch lever 4l as illustrated, and having its opposite end in contact with the cam 47, said lever being lield pressed against the cam by a retractile spring 5l secured at its opposite end to a post 52. The cam 47 is soar-ranged on the shaft 42 that when the temperature reaches a predetermined degree, the cam Will rotate until the end ot the lever 5() drops into the notch 48. 'l`his ii'iovei'nent of lever 5() frees the locking lever 4l so that the escapement wheel may rotate to set the gong in operation as above described. rIlhe gong Will consequently be sounded at predeterminal intervals as controlled by the period of the oscillation of the palletequipped locking lever 4l. Y

In order to stop the operation ot the device and at the saine time reset the trip mechanism a slialit- 53 is `iournaled at its opposite ends in plates 5 and G, and at one end said shaft projects through the base plate 'l and at its extremity is iitted with an operating` knob 54. The shaft 53 carries a cam 55 in the saine plane as the levers 41 and 50, said cam being normally held in inoperative position against a stop pin 56 as shoivn in Figure 3, by a spring 57 coiled on said shaft. When the shalt is rotated in the direction oi the arrow, the cam 55 first strikes the lever 4l and moves it in the direction ot the arrow appended thereto, and continued mov-ement ot the cam While n'iaiiitaining the lever 4l in repressed position device is read" for lfiirthcr operation.

Under some circumstances it may be desirable to provide therinostatically controlled switches at points remote 'from the gong so vthat should an undue temperature develop at any oit such points, the gong will be oporated. -In order to eilect operation of the gong, it Will be obvious that the cam 47 must be rotated until the end of lever 5() drops into the notch 48, and one means of accomplishing` this result is illustrated in Figure 5, a trag mental view indicating the Cain 47, the thermostat 45 and end ot lever Integrally formed With the upper iace of the cam 47 and projecting therefrom, is a lever arm 58 carrying an electrical-magnet pole-piece 59 `lor attraction by an electrical-magnet 60. Upon the closing of an electrical circuit through the magnet, it Will be evident that it will attract the Jole-niece 59 and 'effect rotation oit 'the thermostat shaft to trip the alarm mechanisni in thesame maiinei as if tripped by eX- pansion of the thermostat. `When the circuit is broken, the devi-ce may be reset as above described and Will'be ready ior further operation.

From the above description it ivill be apparent that I have produced a device possess ing all the 'features ot advantage set forth as desirable and, while l have described and claimed the preferred embodiment of the saine, it is to be understood that I reserve the right to make all changes properly falling Within the spirit and scope of the appended claims.

I claim:

l. The combination oi a spring motor, of a gong operated by said motor, escapeinent mechanism to control operation of the motor, means to prevent operation oi". said escapeinent, a cam for eilecting release ot said lastnamed means, and a thermostat for actuating `said cani. i

2. The combination of a springl motor, ot a gong operated by said motor, means to lock the motor against operation, means to trip said locking means, and thermostatic means to release the last-named means.

3. The combination with a spring motor, of a gong operated by said motor, an escapement to prevent operation of the motor, a cam to prevent operation of the escapement, and a thermostat to effect operation of the cam. Y

4. The combination with a spring motor, ot' a gong operated by said motor, an escapeinent to prevent operation oi'"i the motor, a lever normally holding` the escapement against operation, a cani normally retaining the lever in locked position, and a thermostat for effecting' operation of said cam.

5. The combination with a spring motor, of a gong'operated by said motor, means to lock the motor against operation, means to trip said locking means, thermostatic means to release the lastnained means, and mare ually-operable means to move the locking and tripping means to permit the thermostat operated means to return to normal position.

In testimony whereof I ailin my signature.

COLONEL GLENN RGWAN. 

